Investigation of del22 frequency with FISH method in conotruncal heart anomaly patients

Conotruncal heart defects (CTHDs) represent 10-15% of congenital heart diseases and are often associated with genetic syndromes with deletion of the 22nd chromosome (Del22) in the case of DiGeorge velocardiofacial syndrome. Classical conotruncal heart defects include tetralogy of Fallot (TOF), pulmonary atresia with ventricular septal defect (PA-VSD), truncus arteriosus (TA) and discontinuous aortic arch (IAA). The aim of our study was to investigate the prevalence of 22q11.2 deletion by FISH method in children who were followed up due to CTHDs. In 104 cases with CTHDs, 22q11.2 region was examined for deletion by FISH analysis using DiGeorge-VCFS TUPLE1 probe, a specific probe for this region. In patients with CTHDs; in the FISH analysis in group 1 with isolated cardiopathy Del22 was detected in 3 cases, in group 2 with cardiopathy + dysmorphism in 2 cases, in group 3 with cardiopathy + immunodeficiency + dysmorphism in 2 cases and in group 4 with cardiopathy + immunodeficiency in 1 cases Del22 was detected with FISH analysis. Del22 was detected in 8 (7.5%) of 104 patients with congenital heart anomalies. In conclusion, our findings are consistent with the literature. The clinical presentation of Del22 has been found to be highly variable. In addition, various organ systems may accompany this syndrome. For early intervention and disease management, it is important to diagnose the deletion as early as possible. Since the seriousness of cardiac anomalies shortens the life of the patients, we recommend performing Del22 screening with FISH for selective conotruncal anomalies in addition to chromosome analysis. Key Words: DiGeorge syndrome, Del22, FISH, Conotruncal heart defects.